Packets of Promise

Tips on what bulbs to plant and when

It’s time to plant garlic and shallots — and other kinds of bulbs, as well. It’s inspiring, tucking those little bulbs in the ground with thoughts of future good eating and so is tucking bulbs in the ground amidst visions of spring flowers. I’ve enjoyed the ritual of fall bulb planting as long as I can remember and look forward to it every year. If you are not in the habit, though, the window for buying and planting spring-flowering bulbs is easy to miss. When you spot the first daffodils in bloom it’s a little late to ask “How do I get some of those in my garden?” True, you can buy some bulbs in spring, potted and ready to flower. But they are more expensive that way, and the range of varieties available in pots is limited.

Most stores display bulbs for fall planting from September through Thanksgiving. October usually provides a pretty good selection. And it’s not too late to order bulbs from mail order companies, which vastly increases your choice of varieties. It’s a bit late to plant the smallest, earliest blooming bulbs. Snowdrops, in particular, don’t like prolonged dry storage. If you can, plant growing snowdrop bulbs in spring, either purchased in pots or dug from another garden. Crocus “bulbs” (they are corms, really) handle the dry state better. Check that the corms are firm but not brittle, and plant them as soon as possible.

For daffodils and ornamental onions, among others, October is optimal. Tulips can wait until November (or even later, if you must) unless you are planting them in unprotected pots outside, in which case October is best. Pots cool down quickly as the weather cools, slowing root growth, and tulips are more frost resistant once they have grown roots.

In mild climates, hardy bulbs need to be chilled at about 40 degrees for many weeks before planting. I think the Willamette Valley is on the borderline, zone-wise, for pre-chilling, and planting bulbs after the recommended 10 to 12 weeks in the cold often means planting in December, when our soils are already wet and cold. I prefer to keep the bulbs in a cool (but dry) place until I plant them, and hope for the best. Some years, I suspect they might have done better with pre-chilling, but it’s difficult to know for sure.

There are several more predictable causes of failure with bulbs than a lack of pre-chilling. Selecting a site with inadequate light or poor drainage, for example. Most larger bulbs need sunshine, and well-drained soil that is not too acidic. If you want them to return another year, the leaves need ample light while they are green and growing, so avoid locations where bulky perennials may over-top them. A location in full sun is best for most bulbs in our climate, where spring is so often cloudy. Most bulbs will do fine in areas without summer irrigation; tulips and ornamental onions prefer it. Just make sure they get plenty of moisture in spring, until the foliage turns brown.

Daffodils (narcissus), summer snowflake (leucojum), Asiatic lilies, tulips and ornamental onions (allium) are all easy to grow in decent soil. Deer usually leave daffodils, leucojum and alliums alone. Bury all of them under several inches of soil, at least two or three times the height of the bulb. Lilies and tulips do very well in pots, where they don’t need to be planted quite so deeply. In either case, plant them with the bottom (root side) down. And if you can’t tell which is the top (it’s usually at least a little pointy), plant them on their sides!

Choosing what to plant is largely a matter of taste, but there are a few practical considerations. Given our frequently wet and stormy springs, sturdy and rain-resistant varieties are my top choice. That means avoiding very large blooms on tall stems, especially early in the season. Daffodils from the cyclamineus group — such as ‘Jetfire,’ yellow with an orange cup, and all-yellow February Gold — are early flowering, short stemmed and sturdy, unlikely to be felled by rain. Watch out for newer varieties with a pink or apricot cup: ‘Cotinga’ has a white perianth, ‘Prototype’ light yellow.

Among larger, later daffodils, ‘Fortune’ (yellow with an orange cup) and ‘Ice Follies’ (white and cream) are sturdy veterans that are hard to beat for year after year of bloom. Many early tulips are sensibly short-stemmed, but the showiest early tulips are the Emperor series. ‘Orange Emperor’ provides a terrific shot of color in a grey season. ‘White Emperor’ is just plain elegant — and tough.

Ornamental onions (which often go by allium, the genus name for onions) bloom in later spring, coinciding with (and mostly outlasting) late season tulips. The larger alliums are famous for producing some outlandish flower forms, and all of them are fun. The most visually stunning are tall-stemmed purple globes, such as ‘Globemaster.’ But best value for money among these is ‘Purple Sensation,’ not quite so large but much more reliably perennial.

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